Retrofitting heat exchangers such as steam condensers includes removing old heat exchange tubes and replacing them with new heat exchange tubes. Since retrofitting takes place 10 to 20 years or more subsequent to the design of the heat exchanger, it is desirable to take advantage of any improvements in heat exchange tubes when retrofitting a condenser. Frequently the new heat exchange tubes are made from a different material as compared with the old heat exchange tubes and have different characteristics. The new heat exchange tubes are frequently more flexible and/or have thinner walls than the old heat exchange tubes. If the new heat exchange tubes are merely substituted for the old tubes, various problems can occur such as vibration between tubes at the mid span between adjacent support plates.
When retrofitting a heat exchanger, there is no practical way in which a new support plate may be introduced into the heat exchanger shell between the existing support plates to provide the necessary support for the new tubes. Even if the new tubes are identical with the old tubes, it is desirable to provide added support for the new tubes within the shell to minimize any vibration. Heat exchangers designed 20 or more years ago were frequently constructed in a manner so that the distance between adjacent support plates was as much as 60 inches whereas present technology suggests that the support plates be not more than about 30 inches apart.
The problem solved by the present invention is how to retrofit a heat exchanger to provide the desired support within a shell without involving time-consuming and costly disassembly of the maze of hotwell support pipes and other structure.